README
¶
persist/datastore
Google Cloud Datastore persistence with native TTL support.
Features
- Scales automatically, native TTL support
- JSON encoding with base64 for binary safety
- Streaming loads for warmup
- Works across Cloud Run instances
Usage
import (
"github.com/codeGROOVE-dev/fido"
"github.com/codeGROOVE-dev/fido/persist/datastore"
)
// cacheID becomes the Datastore database name
p, _ := datastore.New[string, User](ctx, "myapp")
// Optional: clean up stale entries on startup
p.Cleanup(ctx, 24*time.Hour)
cache, _ := fido.New[string, User](ctx,
fido.WithPersistence(p))
TTL Setup (Recommended)
gcloud firestore fields ttls update expiry \
--collection-group=CacheEntry \
--enable-ttl \
--database=myapp
One-time setup per database. Datastore deletes expired entries within 24 hours.
Fallback Pattern
p, err := datastore.New[string, User](ctx, "myapp")
if err != nil {
p, _ = localfs.New[string, User]("myapp", "")
}
Key Constraints
- Maximum key length: 1500 characters (Datastore limit)
Documentation
¶
Overview ¶
Package datastore provides Google Cloud Datastore persistence for fido.
Index ¶
- type Store
- func (s *Store[K, V]) Cleanup(ctx context.Context, maxAge time.Duration) (int, error)
- func (s *Store[K, V]) Close() error
- func (s *Store[K, V]) Delete(ctx context.Context, key K) error
- func (s *Store[K, V]) Flush(ctx context.Context) (int, error)
- func (s *Store[K, V]) Get(ctx context.Context, key K) (value V, expiry time.Time, found bool, err error)
- func (s *Store[K, V]) Keys(ctx context.Context, prefix string) iter.Seq[string]
- func (s *Store[K, V]) Len(ctx context.Context) (int, error)
- func (s *Store[K, V]) Location(key K) string
- func (s *Store[K, V]) Range(ctx context.Context, prefix string) iter.Seq2[string, V]
- func (s *Store[K, V]) Set(ctx context.Context, key K, value V, expiry time.Time) error
- func (*Store[K, V]) ValidateKey(key K) error
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Store ¶
type Store[K comparable, V any] struct { // contains filtered or unexported fields }
Store implements persistence using Google Cloud Datastore.
func New ¶
func New[K comparable, V any](ctx context.Context, cacheID string, c ...compress.Compressor) (*Store[K, V], error)
New creates a new Datastore-based persistence layer. The cacheID is used as the Datastore database name. Optional compressor enables compression (default: no compression).
func (*Store[K, V]) Cleanup ¶
Cleanup removes expired entries from Datastore. maxAge specifies how old entries must be (based on expiry field) before deletion. If native Datastore TTL is properly configured, this will find no entries.
func (*Store[K, V]) Flush ¶
Flush removes all entries from Datastore. Returns the number of entries removed and any error.
func (*Store[K, V]) Get ¶
func (s *Store[K, V]) Get(ctx context.Context, key K) (value V, expiry time.Time, found bool, err error)
Get retrieves a value from Datastore.
func (*Store[K, V]) Keys ¶ added in v1.11.0
Keys returns an iterator over keys matching prefix. Implements PrefixScanner[V] interface (only usable when K is string). Uses Datastore keys-only query for efficiency.
func (*Store[K, V]) Location ¶
Location returns the Datastore key path for a given cache key. Implements the Store interface Location() method. Format: "kind/key" (e.g., "CacheEntry/mykey").
func (*Store[K, V]) Range ¶ added in v1.11.0
Range returns an iterator over key-value pairs matching prefix. Implements PrefixScanner[V] interface (only usable when K is string). Uses Datastore full query to fetch entities.
func (*Store[K, V]) ValidateKey ¶
ValidateKey checks if a key is valid for Datastore persistence. Datastore has stricter key length limits than files.
Source Files